JP2001293530A - Manufacturing method of heat sink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method capable of obtaining a plate fin heat sink of a wide width type without using a large die. SOLUTION: Extruded shape materials 10, in which a base plate 11 is circular arc and many plate fins 12 are radially extended, are used in two pieces and are integrated by friction stir welded end edges 111 of the base plates 11 parallel to the plate fins 12. The method consists of a joining process and a straightening process to straighten the integrated extruded shape material so as to flatten the base plate 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a wide-width type plate fin type heat sink using an extruded material.

[0002]

2. Description of the Related Art As a method for obtaining a plate fin type heat sink 5 having a high fin height H and a small fin pitch P as shown in FIG. 9, a die 2 as shown in FIG. A method in which a base plate 11 as shown in FIG. 11 produces an arc-shaped extruded profile 100 and corrects the base plate 11 to be flat,
It is known as described in JP-A-11-347626. In the heat sink 5, for example, H = 45 m
m, P = 6-7 mm, W = 200 mm. The bearing 21 formed on the die 2 in FIG. 10 has the same shape as the longitudinal section of the extruded member 100. The bearing 21 is provided with each part 211 for forming the plate fin 12.
Are set so that a portion A between the front ends of the portions has a strength not to be damaged by the pushing load and a width between the base ends of the portions 211 is the same as the target fin pitch P. By letting the metal material pass through the bearing 21, the extruded profile 100 of FIG. 11 is obtained. On the other hand, the joining of members having curved surfaces by friction welding is disclosed in Japanese Patent Application Laid-Open No. 11-267858.

[0003]

However, depending on the use environment of the heat sink, there is a case where a heat sink having not only a high fin height H and a small fin pitch P but also a large width W (FIG. 9) is desired. . However, in the above-described method, in order to obtain a heat sink having a large width W, it is necessary to use a large die 2, which requires a large amount of manufacturing work, and the size of the die 2 that can be used is limited. For this reason, the width W was naturally limited.

An object of the present invention is to provide a manufacturing method capable of obtaining a plate fin type heat sink having a large width W, that is, a wide type, without using a large die.

[0005]

According to the first aspect of the present invention,
A method of manufacturing a heat sink by using a plurality of extruded profiles having a base plate having an arc shape and a large number of plate fins extending radially on the convex side thereof, and using a plurality of extruded profiles. A joining step of integrating the edges of the base plate parallel to the plate fins by friction stir welding, and a straightening step of straightening the integrated extruded profile so that the base plate becomes flat. A method for manufacturing a heat sink, comprising:

According to a second aspect of the present invention, in the first aspect of the present invention, in the joining step, the fins are deformed by receiving a load of frictional stirring in a state where the edges are abutted and restrained. A backing jig is used. The backing jig is a T-shaped jig composed of a substrate and a projecting plate. The projecting plate is inserted between plate fins located at the above-mentioned edges, and the substrate is placed near the above-mentioned edges. The length of the plate fins on both sides of the protruding plate is adjusted so that the plate fins do not bend against the substrate due to thermal expansion during friction stir welding. It is set shorter than the fin.

According to a third aspect of the present invention, in the first aspect of the present invention, in the joining step, the plate fins located at the edges are overlapped with each other, and friction stir welding is performed in that state.

[0008]

FIG. 1 is a front view of a plate fin type heat sink 1 having a high fin height H, a small fin pitch P, and a large width W. FIG. Specifically, for example, H = 45 mm, P = 6 mm, W = 200 m
m.

The heat sink 1 having the above structure is manufactured as follows. First, an extruded member 10 having the shape shown in FIG. 2 is manufactured. The extruded profile 10 has a shape in which a base plate 11 has an arc shape and a large number of plate fins 12 extend radially on the convex surface side. The extruded member 10 is manufactured using the extrusion die 2 shown in FIG. The bearing 21 formed on the die 2 has the same shape as the longitudinal section of the extruded member 10. The bearing 21 is provided with each part 2 forming the plate fin 12.
The portion A between the distal ends of the portions 11 is set to have a width having strength not to be damaged by the pushing load, and the width between the base ends of the portions 211 is the same as the target fin pitch P. By passing the metal material through the bearing 21, the extruded member 10 shown in FIG. 2 is obtained. Here, two extruded members 10 are produced.

Next, the two extruded members 10 are joined and integrated. That is, as shown in FIG. 4, the edge 1 of the base plate 11 is parallel to the plate fin 12 of the extruded profile 10.
11 are butted against each other, the butted portion 112 is restrained by the steel backing jig 3, and the tip projection 41 of the rotary tool 4 is inserted into the butted surface of the butted portion 112. In this state, the rotary tool 4 is rotated. By stirring, the edges 111 are friction stir welded to each other. The backing jig 3 is for supporting the load of friction stirring in a state where the edges 111 are abutted and constrained to prevent deformation of the plate fins 12.

The backing jig 3 comprises a substrate 31 and a protruding plate 3.
2 and a protruding plate 32 with an edge 11
In addition to being inserted between the plate fins 121 located at the position 1, the substrate 31 is used to abut on the tip of the plate fin 12 located near the edge 111. Then, in that case, the plate fins 121 on both sides of the protruding plate 32
Is set shorter than the other plate fins 12 so that the plate fins 121 do not bend by pressing against the substrate 31 due to thermal expansion during friction stir welding.
This setting may be performed when the extruded profile 10 is obtained, or may be performed by shaving after the extruded profile 10 is obtained.

Further, by using the backing jig 3,
The joining depth between the edges 111 is so deep that it penetrates through the thickness direction of the base plate 11. However, if a shallow joining depth is sufficient, the backing jig 3 may not be used.
In that case, the work of attaching and detaching the backing jig 3 becomes unnecessary, so that the entire work is simplified, and the deformation of the plate fin 12 due to the contact with the backing jig 3 is prevented. You. However, in this case, the joining depth is set to be equal to or greater than a depth at which sufficient strength can be ensured even when the surface of the base plate 11 opposite to the plate fins 12 is cut.

Then, the arc-shaped base plate 11 of the extruded profile 20 formed by integrating the two extruded profiles 10 is flattened by the straightening device 6. The straightening device 6 is substantially the same as the straightening device described in JP-A-11-347626. That is, as shown in FIG.
Includes a mounting table 61 on which the extruded profile 20 is placed with its convex surface facing upward, and a pressing portion 62 for pressing the extruded profile 20 on the mounting table 61 downward. Mounting table 61
Has a pair of pedestals 611 and 612 that support both end edges of the extruded profile 20 respectively. A pair of pedestals 611, 6
Numeral 12 is slidably fitted to the horizontal rod 613 via a bearing (not shown). At both ends of the horizontal rod 613, stoppers 614 and 615 are provided fixed to the substrate 616. Springs 617 and 618 fitted to the horizontal rod 613 are provided between the pedestal 611 and the stopper 614 and between the pedestal 612 and the stopper 615, respectively. As shown in FIG. 6, a cutout 7 is formed at an inner corner of the upper portion of the pedestal 611, where the edge of the extruded shape member 20 contacts. The notch 7 includes a first tapered portion 71, a right angle portion 72, and a second tapered portion 73. The pedestal 612 is also formed with a notch 7. The pressing portion 62 is configured by joining a plate-shaped pressing member 623 to the lower surface of a movable plate 622 that can move up and down along a vertical rod 621 fixed to a substrate 616. The lower surface of the pressing member 623, that is, the pressing surface 624, is slightly convex downward. The movable plate 622 is normally driven by hydraulic pressure, but may be driven by air pressure, water pressure, or a power press. The pressing member 623 is usually made of bakelite.

In the straightening device 6 having the above configuration, first, as shown in FIG. 5, both ends of the extruded section 20 are formed in the notches 7 of the pair of pedestals 611 and 612 facing each other at a predetermined interval. Abut. As shown in FIG. 6, the edge of the extruded shape member 20 abuts on the first tapered portion 71. As a result, the extruded shape member 20 is supported by the pedestals 611 and 612, that is, placed on the placing table 61.

Next, the movable plate 622 is driven down.
The pressing surface 624 of the pressing member 623 is brought into contact with the tip of the plate fin 2 of the extruded profile 20, and the extruded profile 20 is pressed downward by the pressing member 623. At this time, pedestal 6
11, 612, while supporting both end edges of the extruded section 20, while resisting the repulsive force of the springs 617, 618,
Go away from each other. As the extruded profile 20 is pressed, the radius of curvature of the base plate 11 increases,
The base plate 11 becomes flat. At this time, both end edges of the extruded profile 20 abut on the right-angled portions 72 of the cutouts 7 of the pedestals 611 and 612.

Then, the pressing is further continued, and the extruded profile 20
Are brought into contact with the pressing surfaces 624. As a result, the base plate 11 of the extruded profile 20 is slightly convex downward. This convex shape is the same as the convex shape of the pressing surface 624, and the convex shape of the pressing surface 624 is such that the base plate 11 of the extruded profile 20 is reduced by the amount corresponding to the springback of the pressed base plate 11 of the extruded profile 20. It is set to be convex downward. Then, the movable plate 622 is raised and the extruded member 20 is removed. As a result, the flat extruded member 20 shown in FIG. 1, that is, the wide-width plate-fin heat sink 1 is obtained.

As described above, according to the above-described manufacturing method, the base plate 11 joins two arc-shaped extruded profiles 10 by friction stir welding to produce a wide-width extruded profile 20, and the extruded profiles 20 are formed. Since the 20 base plates 11 are flattened, a wide-width type plate fin heat sink 1 can be obtained without using a large die 2.

Further, the length of the plate fins 121 on both sides of the protruding plate 32 of the backing jig 3 is changed to the other plate fins 12.
Since the length is set to be shorter, even if the plate fin 121 thermally expands during friction stir welding, the plate fin 121 is not pressed against the substrate 31 and bent.

As the extruded material 10, a plate fin 12 itself is formed at the end of the edge 111, and the plate fins 12 are overlapped with each other as shown in FIG. Stir welding may be performed. According to this, since the plate fins 12 are overlapped with each other, the strength of the portion where the friction stir welding is performed is improved, so that the backing jig can be unnecessary.

In the above manufacturing method, two extruded members 10 are joined. However, three or more extruded members 10 may be joined if necessary.

[0021]

According to the first aspect of the present invention, a plurality of extruded profiles whose base plate is arc-shaped are joined by friction stir welding to produce a wide-width extruded profile, and the base plate of the extruded profile is formed. Since it is flattened, it is possible to use a wide type, especially a width W of 200 m, without using a large die.
m or more can be obtained.

According to the second aspect of the present invention, even if the plate fins on both sides of the backing jig are thermally expanded during friction stir welding, the plate fins are pressed against the substrate of the backing jig and bent. Never. Therefore, deformation of the plate fin can be prevented.

Further, since the backing jig is used, a sufficient joining depth by friction stir welding can be obtained between the edges of the base plate. Therefore, sufficient bonding strength can be secured.

According to the third aspect of the invention, the strength of the portion where the friction stir welding is performed can be improved, and therefore, the backing jig can be eliminated.

[Brief description of the drawings]

FIG. 1 is a front view of a heat sink obtained by a manufacturing method of the present invention.

FIG. 2 is a front view of an extruded profile used in the production method of the present invention.

FIG. 3 is a front view of an extrusion die used to obtain the extruded profile of FIG. 2;

FIG. 4 is a perspective view showing a process of friction stir welding two extruded members of FIG. 2;

FIG. 5 is a front view showing a process of correcting the wide-width extruded profile obtained in FIG.

FIG. 6 is an enlarged front view showing a pedestal of the straightening device used in FIG.

FIG. 7 is an enlarged front view of an edge portion of the extruded profile of FIG.

FIG. 8 is a front view showing another example of the manufacturing method of the present invention.

FIG. 9 is a front view of a conventional heat sink.

10 is a front view of an extrusion die used to obtain an extruded profile for obtaining the heat sink of FIG. 9;

FIG. 11 is a front view of an extruded profile obtained by using the die of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat sink 10, 20 Extruded profile 11 Base plate 12 Plate fin 111 Edge 3 Backing jig 31 Substrate 32 Veneer

Continued on the front page (72) Inventor Nao Tanaka 5-11-3 Shimbashi, Minato-ku, Tokyo Sumitomo Light Metal Industries Co., Ltd. (72) Inventor Shiro Matsumoto 3-9-39 Mikuni Honcho 3-chome, Yodogawa-ku, Osaka-shi, Osaka No. F Term in Japan Aluminum Co., Ltd. (Reference) 4E067 BG00 DA13 DD02 EB00 5F036 AA01 BB05 BC01

Claims (3)

[Claims] 1. A method of manufacturing a heat sink by using a plurality of extruded members each having a base plate having an arc shape and a large number of plate fins extending radially on a convex surface side thereof. A joining process in which the shapes are integrated by friction stir welding the edges of the base plate parallel to the plate fins, and a process of straightening the integrated extruded shapes so that the base plate becomes flat. And a method of manufacturing a heat sink. 2. In a joining step, a backing jig is used to prevent deformation of the fin by receiving a load of friction stir in a state where the edges are abutted and restrained, and the backing jig is a substrate. And a protruding plate, and the protruding plate is inserted between the plate fins located on the edge, and the substrate is used to abut on the tip of the plate fin located near the edge. 2. The method for manufacturing a heat sink according to claim 1, wherein the length of the plate fins on both sides of the protruding plate is set shorter than the other plate fins so that the plate fins are not bent by being pressed against the substrate due to thermal expansion during friction stir welding. . 3. The method for manufacturing a heat sink according to claim 1, wherein in the joining step, the plate fins located at the edges are overlapped with each other, and friction stir welding is performed in that state.